Vat dye.



chl'orid, chloro-,

WILHELM BAUER, or VOHWINKEL, AND ALFRED Hanan? L l i ELBERFELD, GERMANY,ASSIGNORS 'ro rAnnnnrAnaikfan vo na,riunna ii vnn & (70., OF ELBERFELD,GERMANY, .A COR VAT DYE.

No Drawing.

- T0 aZZ whom it may concern:

Be it known that we, VVILHELM BAUER, residing at Vohwinkel, and ALFREDHanna and RUnoLF MAYER, residing at Elberfeld, Germany, doctors ofphilosophy, chemists, citizens of the German Empire, have invented newand useful Improvements in Vat Dye, of which the following is aspecification.

Our invention relates to the manufacture and production of new andvaluable vat dyestuffs. They are obtained by condensing isatinderivatives in which the oxygen of the alpha-keto group isreplaced byeasily movable or replaceable substituents, g. halogen, sulfur, theamino group, the alkoxy group, with carbazol compounds, especiallycarbazol and its halogen substituted derivatives The new dyes are in adry state dark violet crystalline powders with a metallic luster whichare soluble in hot chlorobenzene generally with a violet coloration, andwhich yield with hydrosulfite and caustic soda lye vats dyeing cottonafter'exposure carbazol Other carbazol compounds may be'used, e. g.chlorocarbazol, bromocarbazol, dichlorocarbazol; and instead of theabove isatin derivatives others may be used, 6. g. isatinbromo-,chlorobromoor dichloro isatinchlorid, ortho bromo paramethylisatinchlorid, tri birom'o isatinchlorid, para bromo ortho methylisatinchlorid, etc.

We claim 1. The new dyestuffs being condensation products of isatinderivatives in which the oxygen of the alpha-keto group is replaced byeasily replaceable substituents and a carazol compound, which dyestufi'sare in a dry state crystalline powders with a metallic luster whichare-soluble in hot chlorobenzene generally with a violet coloration andwhich yield with hydroaulfite and caustic soda lye vats dyeing cottonafter xposure to airred to violet shades remark- A PORATIONI orennmpecification of Letters Patent.

Application filed April 5, i912. SerialNo. 688,770. I

their fastness to chlorin.

In order to illustratethe new process more fully we can proceed asfollows, the parts being by"weight: 305"'parts fof dibromoisatin areconverted' in" a dry-benzene suspension into dibromoisatiii chlorid byheating it with 220 parts P015. The mixture thus obtaineddsafter coolingpoured into a hot solutionwhich is"well stirredof 180 parts of carbazol'in3,000 parts ofdry chlorobenzene. for a short time andth'e' "dyewhichlseparates on, coo-ling is filtered oil and washed. his a violetcrystalline powder with winetallic luster inelting at,269 CL soluble-inhot chlorobenzene withi'a .violettand" in concentrated sulfuric'a'cidwith, a greenish-blue coloration. It yields -with' hydrosulfite and NaOII a yellow vat from which cotton is dyed yellow changing on exposureman into a fast deep Bordeaux-red fast to chlorin.

The formation of the new dye may be illus trated by the followinggraphic equation.

able for their fastness to chlorin, substantially as described.

2. The new dyestuffs being condensation to air red to violet shad'esremarkable for The stirring is continued are soluble in hotchloro-benzene generally a with a violet coloration, and WhlCh yieldwith hydrosulfite and caustic soda lye vats dyeing cotton after exposureto air red to 'violetshades remarkable for their fastness to chlorin,substantially as described.

3. The new dyestufi'sbeing condensation products of apoly-halogei1-substituted isatin derivative in which the oxygen of thealphaketo group is replaced by easily replaceable substituents and acarhazol compound, which dyestufis are in a dry state crystalline-pemzders with a metallic luster which are soluble in hot ehloro-benzenegenerally ,with a violet coloration, and which yield to chlorin,substantially as described.

.4. The new dyestuffs being condensation products of a'di-halogensubstituted isatin derivative in which the oxygen ofthealphaketo group is replaced by easily replaceable substit'uents "anda carbazol compound, which dyestuffs are in a dry state crystallinepowders with a metallic luster which are soluble in hot chloro-benzenegenerally with a violet coloration, and which yield with hydrosulfiteand caustic soda lye vats dyeing cotton after exposure to air red toviolet shades remarkable for their fastness to chlorin, substantially asdescribed.

5. The new dyestuffs being condensation products of abro-mo-halogen-substituted isatin derivative in which the oxygen of thealpha-keto group is replaced by easily replaceable substituents and aoarbazol compound, which dyestuffs are in a dry state crystallinepowders with-a metallic luster which are soluble in hot chloro-benzenegenerally with a violet coloration, and

which yield With hydrosulfitc and caustic soda lye vats dyeing cottonafter exposure to air red to violet shades remarkable for l Br.

' exposure to air into a deep Bordeaux-red remarkable for its fastnessto chl'orin, substantially as described.

In testimony whereof we have hereunto set our hands in the presence oftwo subscribing witnesses.

WILHELM BAUER. [1 s] ALFRED HERRE. a s] R'UDOLF MAYER. v 1,. 3.

lVitnesses:

HELEN Norma, ALBERT NUFER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of lt'aten'ts,

Washington, D. G."

